TOPIC: Open discussion on MOSAN toilet design

Working throughout Africa since 1996 in development cooperation. Involved with sustainable sanitation systems since 2002. Currently working for the AHT GROUP AG (a private consultancy office in Germany).

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hi Lukas,
I'll be in Zambia soon on a short term mission for the GIZ water programme out in Chipata looking at rural sanitation. I'd be interested in hearing what progress you may have made so far. Please mail me at bracken@aht-group.com.
Thanks.
Patrick

I think it might be helpful to consider the types of disabilities shown when designing a supportive structure for the people with disability. In some cases people that normally use wheelchairs crawl around on all fours since the houses are to cramped or the floors to uneven to use a wheel chairs. This means they will have to get up on the Mosan toilet from the floor.

Industrial designer with great interest in social innovations. Together with GIZ I designed the MoSan household toilet. Currently based in Zurich.

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Dear readers,

we are finally producing the long-awaited prototypes. Last week the mold for the main pot was milled, the seat is in production right now. On Thursday we will deep-draw the first prototype made from durable ABS plastics. All parts will have different wall-thicknesses to optimize stability, weight and costs. The lid will be produced in the end, after we tested the stability of the seat and the main pot. It could be necessary to chose thicker plastic sheets for deep-drawing and this will affect the size of the lid.

As a "sneak preview" here a picture of the CAD draft.
If you are wondering where the side-handles are: the outer edge between seat and main pot is big enough to grab the toilet and carry it easily.

Industrial designer with great interest in social innovations. Together with GIZ I designed the MoSan household toilet. Currently based in Zurich.

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Dear readers,

please check out the MoSan blog for first results from deep-drawing with thermoplastics! The day at the workshop was great and the results are amazing. I am very happy we took the time to change the process from manual laminating to deep-drawing. With the new way of production the design was optimized:
- all parts are stackable
- surfaces are smooth and easy to clean
- measurements are optimized regarding ergonomic feedback
- simplifications for easier production

Looks great so far, and I see you lowered the interior a bit for male users

Quick remarks:
-Color should definitely be looked into, a light yellow or brown is probably the best.
-How much weight does the new bottom withstand? It looks quite flexible, so there might be a risk of the top slipping partially into it, when uneven pressure is applied from the top.
- I see the grips at the sides where cut from the design... I guess since it will be mostly the containers inside that are moved, that isn't such a big issue, but the mobility inside the house is definitely lowered by that.
-can you post pictures of the lid? I think since this is partially an innovation for the disabled and elderly, special care needs to be taken designing the grip so that it can be used without help. Edit: the easiest for that would probably be the option to attach an additional wire hook to it somehow, which can then be formed for the best usability individually. So two solid flanges which can be drilled for holes to hold the wire would probably be best.

P.S.: If you are interested in a pilot of the new design in urban Kampala (Uganda) we could probably arrange for it. Here in Kampala there are also PE production capacities, so it could be locally produced (if one comes up for funding to make the molds).

Industrial designer with great interest in social innovations. Together with GIZ I designed the MoSan household toilet. Currently based in Zurich.

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Dear Julius,

great, many thanks for your feedback and offering your support for piloting the toilet in Uganda. We should definitely discuss this further by email and skype! Please let me know your email address.

Regarding your remarks,
- Weight: we stressed the toilet (main pot+seat) with 130kg at the workshop. The seat bends slightly and goes directly back to its initial shape. PE has the great property that it is more flexible than brittle. Which means, it is very difficult to break it. I tested this by throwing the toilet on concrete ground, the reaction was, the toilet just "jumped" away without any damage.
- Since the shape of the seat is angled and becomes wider till the edges, the weight distributes evenly and the seat doesn't slip inside the main pot.

- Handles: It is right, the two side handles were removed for several reasons (simpler molds=easier demolding=cheaper production) But instead I designed the outer edge between seat and main pot big enough to work perfectly as a all round handle. This means, even if the toilet is placed at a very narrow space you can lift the toilet from all sides, without being limited to 2 handles. This is meant to add mobility than lowering it!

- Lid: The lid is in production this week. On Friday I can post more pictures! Thanks for this advise. We are currently discussing with GIZ in Zambia to test the MoSan toilet with people with disabilities.

- Colour: The colour is caused by production and not chosen on purpose. White (called "nature") is the most common colour of PE and also the cheapest. All other colours, like black or blue are inked by pigments and are more expensive. If we produce more than 10 prototypes it is of course possible to order colored plastics, but so far it is not feasible. My preferred colour is still a blue-turquoise, since I think it communicates cleanliness, freshness and nature at once

Your toilet appearance and design is very unique! It should be very good in many places. Thanks to this forum for bringing those concerned with seeking simple sanitation together.

Regarding design perfecting as another poster said, the bowl should be deep enough so males sitting on the toilet don't have a problem with skin contact inside the bow. On the toilets I have been devolving this has been an issue, and I simply had to make the bowl deeper than I first thought. It is rare, yet it also happens that the water level in a normal flush stools is too high, and males do not appreciate the resulting physical contact with the water.

In my development it also has been a challenge to put the urine feces divider as the right place. That is to put it back far as possible to intercept as much urine as possible, yet still forward far enough so feces do not end up on the urine pan.

One of the toilets I have been working on is quite a bit like yours (although not as attractive). One difference is that I employ a gate that covers the feces compartment, and which only needs opened for defecating. Admitted this feature has both pro and cons. The cons being a gate needs opened to defecate, and the bowl cannot be quite as nicely rounded. Yet it has the advantage of additional sanitation, as the solid waste area is additionally obstructed and can even remain obstructed when one needs to merely urinate. The gate cuts greatly cuts the odor, while using a minimum of covering material. Another vital advantage of the gate is that more urine is intercepted and less enters the feces area. This also saves mess and covering material and space in the feces container. I believe I can get up to a 98 percent average urine interception with my toilet with the gate. The only time it does not intercept all the urine is when females use it with the gate open for defeceting, then some urine is not interecepted.

@Mona: You can reach me via
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(Ich spreche ebenfalls deutsch). UWASNET could link you up with local NGO/CBOs working in urban slum areas and facilitate the process. However, as a local Ugandan NGO network we do not have a lot of financial means available to directly support this interesting project.